V.F. Kravchenko1 and M.A. Basarab2
1Institute of Radio Engineering and Electronics of the RAS, Moscow
2Bauman Moscow State Technical University, Moscow
Synthesis of Antennas on the Base of the Boolean Algebra Transformations and the Atomic Functions Theory
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V.M. Petrechenko, O.G. Pochanin, G.P. Pochanin, and V.P. Ruban
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Automated System for UWB Antennas Characteristics Measurement
The paper is related to development of the automated system for ultra-wide band (UWB) antennas characteristics investigation. The set of equipment including non-standard, specially developed units and computer software as well as functional capabilities of the system are described.
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A.S. Andrenko1, I.V. Ivanchenko, N.A. Popenko, and M.M. Khruslov
1Fujitsu Laboratories LTD., YRP R&D Center
5-5, Hikarino-Oka, Yokosuka, 239-0847, Japan
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Experimental Investigations of Planar Dielectric Disk Antennae
The results of experimental investigations of planar dielectric disk antennae with different dielectric substrates
and radiating elements are represented. Geometric and electric parameters of antenna prototypes have been chosen
in accordance with the theoretical calculations to provide the conditions of the ÒÌ01 mode excitation
in the electromagnetic structure under study. It has been determined that the use of substrates with different values of
the permittivity gives rise to the change in the antenna patterns and the field intensity in their lobes.
Moreover, the use of dielectric disks with high permittivity ( ed =90) provides an increase in the power radiated into the free space as well as a frequency band enhancement.
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D.N. Makovetskii
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkov 61085, Ukraine
Bistability and Transient Processes in a Three-Level Phaser System Saturated by a Standing Pumping Field and a Signal Traveling Wave
Nonstationary processes in a three-level active paramagnetic phaser system have been investigated in case of the inversion state branching (bistability) which takes place below the threshold of self-excitation of the phonon generation. It has been shown that the nature of the branching of inversion states and transient processes in such a system depends significantly not only on a hypersound signal intensity, that was determined before, but also on a signal modulation frequency. Narrow nonlinear resonances and a critical slowing-down of transient processes have been found at simultaneous saturation of a spin-system by a standing electromagnetic pumping field and a hypersound-signal traveling wave.
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A.A. Bondarev, I.V. Ivanchenko, S.Yu. Karelin, and N.A. Popenko
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkov 61085, Ukraine
A Bistability Phenomenon in a Resonator with a Non-Linear Semimagnetic Semiconductor
The numerical simulation of characteristics of a three-mirror resonator with a non-linear semimagnetic semiconductor has been carried out. The conditions for the occurrence of bistability states in the resonator, stipulated by the excitation of a spin-magnetoplasma wave on the semimagnetic semiconductor/dielectric boundary, have been determined. It has been shown that this resonator can be used as a trigger or a limiter in the devices and the systems of the terahertz-wave band, characteristics of which can be controlled by the variation of the external magnetic field.
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A.V. Shvets1, A.P. Nickolaenko1, G.G. Belyaev2, and A.Yu. Schekotov2
1A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
2Institute for Terrestrial Magnetism, Ionosphere and Radio Propagation (IZMIRAN)
Troitsk, Moscow region, 142190, Russia
Analysis Schumann Resonance Parameter Variations Associated with Solar Proton Events
Detailed analysis is performed of the spectra of natural electromagnetic field in the frequency band of Schumann resonance (SR) during the strongest solar proton events (SPE) from 2000 to 2003. The decline of the peak resonance frequencies associated with SPE was confirmed by simultaneous observations at two globally separated observatories (Karelia and Kamchatka). Effects are substantially different when observed in various field components. The anomalous excursions of the peak resonance frequencies are explained in the framework of propagation theory of ELF radio waves. These changes originate owing to polar non-uniformities in the lower ionosphere
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